N E C  P4,P100 WIRING         
                                                     

                                       1  2  3  4  5  6  
      -----------------------          ----------------
       (O)  1 X X 4 5 6 X X           
      -----------------------          ----------------
                                       7  8  9  X  X  X
         P4 BASE ,KEYS DOWN           P100 BASE ,KEYS UP
        
        P4     P100
REF 1   1       7
REF 4   4       2
REF 5   5       9
REF 6   6       3



 2 x 2N 3904  Tranistors  (Looking at it flat side legs down!)   1 2 3
 2 x IN       Diodes 
 2 x 10k      Resistor



Pin 1  ----------------------------------------------------------|-----|
                                                                 1     |
Pin 2  -- Diode >|------------ Centre Leg Transistor One         0     | 
                                                                 K     | 
Pin 4  -- Diode >|------------ Centre Leg Transistor Two         r     | 
                                                                 e     1
Pin 12 --Leg 3 on Tranistor Two bridged on here -- REF 6  -------s     0 
                                                                       K
Pin 13 ------------------------------------------- REF 4               r
                                                                       e
Pin 15  - Leg 3 on Tranistor One bridged on here - REF 5  -------------s

Pins 18 To 25  ---  Leg 1 Of Trans One & Two  ---- REF 1

N.B. you must bridge pins 18-25 with solder so they are as 1 ok!

BOTH RESISTORS MAY NOT BE NEEDED ON SOME COMPUTOR MODELS
         
REF 1  =   1   7
REF 4  =   4   2
REF 5  =   5   9
REF 6  =   6   3